title: Development of an obeche wood allergen quantification assay for the assessment of allergen exposure in workplaces.
abstract: OBJECTIVE
  The purpose of this study was to develop a quantification assay to measure airborne concentrations of obeche wood allergen at workplaces.
  
  
  METHODS
  Specific polyclonal antibodies to obeche wood were produced in rabbit and used to develop an inhibition enzyme immunoassay (EIA). Inhalable dust samples from three wood-processing companies were taken with a stationary sampling device (Gravicon VC25). The loaded dust filters were extracted under standardized conditions and measured with the assay. In addition, the antigen and allergen contents of obeche wood from different sources (Cameroon, N=5; Ghana, N=4) were analyzed from immunoblots, detected with rabbit immunoglobulin (Ig) G and human Ig E.
  
  
  RESULTS
  Polyclonal antibodies specific for obeche wood allergens, without cross-reactivity to other woods, were used to establish the inhibition enzyme immunoassay. The assay is able to quantify allergen concentrations from 30 to 300 ng/ml. With inhibition enzyme immunoassay, exposure to airborne obeche wood allergen can be monitored in wood-processing companies. Inhalable dust samples from workplaces contained an average allergen concentration of 15 microg/g dust. Significantly lower protein and allergen contents were measured for obeche wood from Cameroon (ayous) in one company. IgE immunoblots indicated that the lower antigen and allergen contents of the ayous wood may be the result of its lacking the major obeche wood allergen, Trip s 1.
  
  
  CONCLUSIONS
  The data showed that the total dust concentration in workplaces containing obeche wood dust did not correspond to the assessed allergen concentration. To estimate exposure limits regarding sensitization risk, it is necessary to measure the allergen content directly.
authors.affiliation: BGFA-Research Institute of Occupational Medicine, German Social Accident Insurance, Ruhr-Universität Bochum, Germany. kespohl@bgfa.de
authors.forename: Sabine
authors.initials: S
authors.lastname: Kespohl
authors.forename: Ingrid
authors.initials: I
authors.lastname: Sander
authors.forename: Johannes
authors.initials: J
authors.lastname: Schulze
authors.forename: Marnix
authors.initials: M
authors.lastname: Poppe
authors.forename: Thomas
authors.initials: T
authors.lastname: Brüning
authors.forename: Monika
authors.initials: M
authors.lastname: Raulf-Heimsoth
mesh_terms: D016902:Air Pollution, Indoor / Q000009:adverse effects*; D000485:Allergens / Q000009:adverse effects*; D001681:Biological Assay; D004391:Dust; D006801:Humans; D007124:Immunoenzyme Techniques; D007073:Immunoglobulin E; D016273:Occupational Exposure / Q000009:adverse effects*; D016272:Occupational Health; D014934:Wood / Q000633:toxicity*; D017132:Workplace
chemical_list: D000485:Allergens; D004391:Dust; D007073:Immunoglobulin E